Internal combustion engines used in automobiles and trucks all employ various systems for pumping oil from a sump through various parts of the engine to lubricate the moving parts. The oil typically is located in the crankcase beneath the engine to which an oil pan or reservoir is attached. This oil becomes dirty and breaks down and must be changed at regular intervals to prolong the life of the engine.
Typical internal combustion engine crankcases have a drain plug located at the bottom of the crankcase at its lowermost point. Usually, the old oil is removed first by placing a funnel or container beneath the drain plug location. The drain plug then is removed to permit the oil to flow out of the bottom of the crankcase by gravity. After the oil has drained out of the crankcase, the plug is replaced; and new oil is poured into the engine from the top. In service stations, a waste drum typically is located on the floor beneath the point where oil is drained from the engine. This waste drum occupies a substantial space in the floor area directly beneath the engine. The drum usually is placed on wheels, so it may be moved out of the way when a vehicle which has been raised on a hoist above the drum location is lowered again to the ground. Even though this is a cumbersome procedure, it is widely used in service stations.
Many automobile and truck owners prefer to change their own oil. For such owners, a hydraulic hoist of the type used in service stations generally is not available. Consequently, a relatively shallow pan or other container is placed on the ground beneath the vehicle and the owner must slide under the vehicle to remove and replace the crankcase drain plug. This is a messy and difficult undertaking for most people. Consequently, changing the oil in motor vehicles most frequently is done in service stations, because of the availability of hoists to lift the vehicle above ground to permit removal and reinsertion of the crankcase drain plug.
Various techniques have been devised in the past for discharging oil from the crankcase without the necessity for getting beneath the vehicle to remove the typical crankcase drain plug. One such approach is disclosed in the U.S. Pat. to Sweetland No. 2,216,360. This patent is directed to a specialized crankcase which has a built in pump and discharge pipe attached for operation from above. The crankcase drain plug is permanently installed in this device. The device of Sweetland, however, requires a non-standard construction of the oil pan, so that it is not capable of simple retrofitting on existing automobiles.
Another patent which is directed to an automatic oil changer, for removing oil from the bottom of the crankcase without the necessity for removing the crankcase drain plug to accomplish the removal, is disclosed to the U.S. Pat. to Burrell No. 3,282,380. The system of Burrell has a permanently attached evacuation hose connected to the opening in the bottom of the crankcase in place of the normal drain plug. This hose then is connected to a direct current pump which may be activated to pump out the oil from the crankcase. A container is mounted in the upper portion of the engine compartment or on the engine block itself to receive the discharged oil from the pump. No valves are provided in the system to prevent oil from the crankcase to drain into the line connected from the crankcase to the pump intake. Consequently, if the line or tube connected between the crankcase drain opening and the pump should develop a leak or become dislodged, it is possible for all of the oil to drain out of the crankcase. If the engine is running when this occurs, the result could be significant damage to the engine.
Two other patents which are directed to nearly identical systems for power removal of oil from the crankcase of an automobile engine without the necessity for elevating the automobile or for removing the drain plug from the crankcase are the U.S. Pat. Nos. to Wood 2,206,992 and Kuklewicz 3,743,053. Each of these patents discloses the use of an adapter, with a ball check valve in it, which is substituted for the drain plug normally used in the bottom of the crankcase. This adapter has a discharge opening in it which is connected to an evacuation line. The evacuation line then is connected to a normally inoperative pump. When the pump is operated, however, the vacuum or suction on the line causes the check valve to open and release the oil from the crankcase. The oil then moves through the line and the pump into a discharge receptacle. Upon termination of the oil evacuation operation, the pump is turned off, the check valve returns to a closed position to close the opening in the bottom of the crankcase, and the crankcase may be refilled with fresh oil. The automobile engine then is operated in its normal manner until the next time evacuation of oil from the crankcase is desired.
The devices of both Wood and Kuklewicz provide an additional degree of protection in the event the evacuation line connected to the adapter should become loose or broken. If this should occur, the check valve will hold the drain opening closed; so that accidental discharge of the oil will not occur. These devices, however, are subject to damage inasmuch as if either of the adapters of Wood or Kuklewicz should strike an obstruction beneath a moving vehicle, the adapter could become broken away. In such an event, the spring holding the ball of the check valve would be released and the drain opening in the bottom of the crankcase no longer would be closed. Oil then could drain out without the knowledge of the vehicle operator and result in damage to the engine.
It also should be noted that the structure of the Kuklewicz check valve cannot readily be manufactured in the form disclosed in Kuklewicz. It is necessary to make the check valve portion of Kuklewicz in either two mating vertical sections or in a separate top section which would somehow be mounted onto the remainder of the body. Otherwise, the spring and ball cannot be inserted into the check valve chamber of Kuklewicz.
In Wood, additional steps are necessary to provide a valve seat for the ball check valve by rolling or peening the upper annular edge of the drainage fitting over the valve seat to hold the valve seat in place. If this is not carefully done, the valve seat may be misaligned and could permit leakage of oil past the ball as a result.
It is desirable to provide an adapter for use with standard automobile crankcases to permit the power evacuation of oil from the crankcase through an opening in its bottom, which overcomes the disadvantages of the prior art, which is reliable in operation, is inexpensive, and which provides an added degree of safety in the event the power drain components connected to it should become dislodged or broken.